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What is the $? (dollar question mark) variable in shell scripting? [duplicate]
...nsider the Bash code:
$ false
$ echo $?
1
The C "equivalent" is:
false.c
#include <stdlib.h> /* exit */
int main(void) {
exit(1);
}
bash.c
#include <unistd.h> /* execl */
#include <stdlib.h> /* fork */
#include <sys/wait.h> /* wait, WEXITSTATUS */
#include <stdio.h&...
How can I get file extensions with JavaScript?
...VisioN's answer below, particularly files with no extension (.htaccess etc included).
It's very performant, and handles corner cases in an arguably better way by returning "" instead of the full string when there's no dot or no string before the dot. It's a very well crafted solution, albeit tough...
Read whole ASCII file into C++ std::string [duplicate]
... a streambuf iterator out of the file and initialize the string with it:
#include <string>
#include <fstream>
#include <streambuf>
std::ifstream t("file.txt");
std::string str((std::istreambuf_iterator<char>(t)),
std::istreambuf_iterator<char>());
N...
How do you write a migration to rename an ActiveRecord model and its table in Rails?
...
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How to sort a list of lists by a specific index of the inner list?
...
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Scatterplot with too many points
...ionanalytics.com/2011/10/ggplot2-for-big-data.html).
(In the following, I include the "points"-layer for illustration purposes.)
library(ggplot2)
library(ggsubplot)
# Make up some data
set.seed(955)
dat <- data.frame(cond = rep(c("A", "B"), each=5000),
xvar = c(rep(1:20,250) ...
Using pre-compiled headers with CMake
...:/foo/bar.h will force you to either pass the /FpC:/foo/bar.h flag or put #include <C:/foo/bar.h> at the top of all of your .cpp files as the first include statement. MSVC does a string compare of the #include arguments, it does not check whether it points to the same file as what was given to...
How to check if the URL contains a given string?
...has a toString() method. So you can do it like this:
(''+window.location).includes("franky")
or
window.location.toString().includes("franky")
From the old Mozilla docs:
Location objects have a toString
method returning the current URL. You
can also assign a string to
window.location...
C++ Convert string (or char*) to wstring (or wchar_t*)
...d with the standard library (C++11 and newer) alone.
The TL;DR version:
#include <locale>
#include <codecvt>
#include <string>
std::wstring_convert<std::codecvt_utf8_utf16<wchar_t>> converter;
std::string narrow = converter.to_bytes(wide_utf16_source_string);
std::ws...
Proper way to rename solution (and directories) in Visual Studio
... Visual Studio is such a powerful program, but this feature is not included? wow..
– Luca Steeb
Jul 20 '15 at 11:25
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